spiralArchimedean
Create Archimedean spiral antenna
Description
The spiralArchimedean
object creates a planar Archimedean
spiral antenna on the xy- plane. The default Archimedean spiral is
always center fed and has two arms. The field characteristics of this antenna are
frequency independent. A realizable spiral has finite limits on the feeding region and
the outermost point of any arm of the spiral. The spiral antenna exhibits a broadband
behavior. The outer radius imposes the low frequency limit and the inner radius imposes
the high frequency limit. The arm radius grows linearly as a function of the winding
angle.
The equation of the Archimedean spiral is:
where:
r0 is the inner radius
a is the growth rate
ϕ is the winding angle of the spiral
Archimedean spiral antenna is a self-complementary structure, where the spacing between the arms and the width of the arms are equal. The default antenna is center fed. The feed point coincides with the origin. The origin is in the xy- plane.
Creation
Description
creates a
planar Archimedean spiral on the X-Y plane. By default, the antenna operates
over a broadband frequency range of 3–5 GHz.ant
= spiralArchimedean
Output Arguments
Properties
Object Functions
axialRatio | Calculate and/or plot axial ratio of antenna or array |
bandwidth | Calculate and/or plot absolute bandwidth of antenna |
beamwidth | Beamwidth of antenna |
charge | Charge distribution on antenna or array surface |
current | Current distribution on antenna or array surface |
design | Design prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects |
efficiency | Radiation efficiency of antenna |
EHfields | Electric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays |
impedance | Input impedance of antenna or scan impedance of array |
info | Display information about antenna, array, or platform |
memoryEstimate | Estimate memory required to solve antenna or array mesh |
mesh | Mesh properties of metal, dielectric antenna, or array structure |
meshconfig | Change meshing mode of antenna, array, custom antenna, custom array, or custom geometry |
optimize | Optimize antenna or array using SADEA optimizer |
pattern | Plot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array |
patternAzimuth | Azimuth plane radiation pattern of antenna or array |
patternElevation | Elevation plane radiation pattern of antenna or array |
rcs | Calculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array |
resonantFrequency | Calculate and/or plot resonant frequency of antenna |
returnLoss | Return loss of antenna or scan return loss of array |
show | Display antenna, array structures, shapes, or platform |
sparameters | Calculate S-parameters for antennas and antenna arrays |
vswr | Voltage standing wave ratio (VSWR) of antenna or array element |
Examples
References
[1] Balanis, C.A. Antenna Theory. Analysis and Design, 3rd Ed. New York: Wiley, 2005.
[2] Nakano, H., Oyanagi, H. and Yamauchi, J. “A Wideband Circularly Polarized Conical Beam From a Two-Arm Spiral Antenna Excited in Phase”. IEEE Transactions on Antennas and Propagation. Vol. 59, No. 10, Oct 2011, pp. 3518-3525.
[3] Volakis, John. Antenna Engineering Handbook, 4th Ed. McGraw-Hill
Version History
Introduced in R2015a